<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
<div style="text-align: center">
    <input type="file" onchange="submit(this)" />
</div>
</body>
<script>
    function submit(ele){
        var form = new FormData();
        form.append("file",ele.files[0]);
        var xhr = new XMLHttpRequest();
        xhr.open("POST","/welfareItem/upload",true);
        xhr.send(form);
    }
</script>
</html>